Optimizing the immobilization of biosurfactant-producing Pseudomonas aeruginosa in alginate beads

Context: Biosurfactants are amphipathic molecules that reduce surface tension. The major reasons to economically production of the biosurfactant are their health, safety, environmental management, and promising applications. Aims: To optimize the immobilization of Pseudomonas aeruginosa as a biosurfactant producer in alginate beads. Methods: Biosurfactant production by P. aeruginosa was confirmed through the hemolysis test, emulsification index, and surface activity measurement. Calcium alginate encapsulation technique was used in order to entrap the P. aeruginosa cells. Full factorial design was employed to optimize bead preparation. Furthermore, the morphology and the stability of beads were evaluated. Results: It was proved that immobilized cells can be preserved the viability and biosurfactant production. Application of full factorial design indicated that the values of three parameters sodium alginate 3%, CaCl2 1% (w/v), and hardening time of 35 min, was found to be too stable for minimum surface tension and stable alginate gel beads. Conclusions: The alginate gel beads showed stability during the growing process and the immobilized cells efficiently were viable. Alginate source, hardening time, and the interaction between CaCl2 concentration and hardening time influenced on the bead preparation.